Tire mounting tool



March 14, 1961 H. G. TWIFORD 2,974,722

TIRE MOUNTING TOOL Original Filed Nov. 15, 1956 2 Sheets-Sheet 1INVENTOR. Harry G. Twiford ATTORNEYS March 14, 1961 H. e. TWIFORD TIREMOUNTING TOOL 2 Sheets-Sheet 2 Original Filed Nov. 15, 1956 INVENTOR.Harry G. Twiford AlTORNEYS 2,974,722 TIRE MOUNTING TOOL Harry G.Twiford, 777 S. Adams St., Denver 9, Colo.

4 Claims. (Cl. 1.57-1.22)

This invention relates to tire-mounting tools and a method of mounting atire on a wheel, and more particularly to tools for and a method ofmountingpneumatic tires on drop-center wheels in such a manner that thebead of the pneumatic tire does not touch the rim of the wheel as it isbeing placed on the wheel.

This application is a divisional application of my copending applicationSerial No. 622,303, filed November 15, 1956, for Tire Mounting Tool, nowPatent No. 2,925,857.

Tubeless tires have recently become standard equipment on newautomobiles and have largely replaced tires requiring an inner tube tohold the air. Since there is no tube used with such tubeless tires, thecontact between the tire bead and the wheel rim is critical since thisconnection may be a major source of leak of air from the tire. Themounting and dismounting of tubeless tires from wheels must be done withextreme caution since any nick or crease on the tire bead will disruptthe seal and will cause a leak between the two members. With the veryrecent trend of the use of smaller wheels, the mounting and dismountingof tires from such small wheels becomes extremely diflicult and manytires are ruined with the tools now available. It is readily seen thatin reducing the diameter of the opening of the tire one inch, thecircumferential extent is reduced by over three inches. The reduction insize makes the mounting and dismounting of the smaller tires on thesmaller wheels extremely difficult, since it has actually reduced thetotal amount of stretch which is necessary to permit the tire bead topass over the rim of a wheel. Also,.the majority of the smaller wheelshave a very sharp rim, and in mounting a tire, the rim frequently cutsand nicks the bead.

According to the present invention, I have discovered a tire-mountingstructure which includes a bead-holding member and a bead-droppingmember which are arranged to operate on a wheel rim for dropping a tirebead over the rim into the drop center of the wheel without having thetire bead touch the wheel rim during the mounting operation. Thetire-mounting tool provides smooth surfaces over which. the bead of thetire may pass without contacting the tire bead with the sharp edges ofthe rim or subjecting the bead impact tools commonly used in placing ahead over the rim of .a wheel. The tiremounting structure quickly andeffectively drops the bead States Patent over the rim of the wheel witha simple rotary movement mechanism for mounting a tire on a wheelwithout impact tools and without cutting or nicking the beads of thetire. The tire-mounting structure provides a plurality of smoothsurfaces over which a tire bead may be dropped 2,974,722 Patented Mar.14, 1961 across the rim of a wheel into mounted position on a wheel. Thetire-mounting structure, also, provides a pick-up mechanism which picksup the bead of a tire being mounted, places it in position to drop overthe rim of a wheel and a eflectively preventing the tire bead fromcoming into contact with the wheel rim during the mounting operation.

These and other objects and advantages of the present invention may bereadily ascertained by referring to the following description and theappended illustrations in which:

' Fig. 1 is a top plan view of the two tire-mounting tools in initialposition on a pneumatic tire wheel;

Fig. 2 is a top plan view of a bead-holding mechanism of the structure;r

Fig. 3 is a partial cross-sectional view of the bead-holding mechanismtaken along section line 3-3 of Fig 2;

Fig. 4 is a side-elevational view of a bead-dropping mechanism; and

Fig. 5 is a top plan view of a bead-dropping mechanism.

In a common tire-mounting process, a wheel is placed in substantiallyhorizontal position, and a tire to be mounted thereon is placed on topof the wheel. One side of the lower bead of the tire is placed over theupper rim of the wheel, and then by various mechanisms the bead of thetire is progressively forced over the remaining part of the rim so, thatthe tire bead is under the rim of the wheel. The construction of thewheel and the tire is such that the rim of the wheel is substantiallylarger than the diameter of the opening of the bead of the tire, so thatwhen the tire is mounted on the wheel the bead of the tire may restlaterally or axially against the rim of the wheel and be held thereon.The process is repeatedwith the upper bead, passing it over one sectionof the rim of the wheel and then progressively forcing the remainder ofthe head of the tire over the rim into the drop center of the wheel.

The device illustrated in Fig. 2 is a bead-holding mechanism which isarranged to be attached to the rim of a wheel and hold a segment of ahead of a tire stationary and in the drop center while the remainingpart of the head is progressively passed over the rim of the wheel. Theholding mechanism includes a body portion 1 which is arranged to lie ona rim and radially of a wheel on which it is mounted. An integral axialor lateral surface 2 extends upwardly from the body. A lower inwardlybiased surface 3 which is arranged to hook over the rim 4 of a wheel isconnected to thebody. An upper bead stop 5 is provided which preventsthe axial movement of the bead away from the rim of the wheel during themounting process. The body is securely attached to the rim 4 by means ofa rim-gripping cam 6 pivotally mounted on the body by means of a pivotmount 7. The rimgripping device includes a handle portion 8 and aconnected cam surface 9 which moves into and out of contact with a rimby movement of the handle portion 8. With the portion 3 hooked over therim 4, the handle 8 is moved in counterclockwise direction so that thecam surface 9 engages the rim and securely locks the body 1 thereon.Since the flanges on the rims of the wheel are not uniform, a levelingcam is provided which includes an axially-directed cam surface 11 and ahandle 12 pivoted on the pivot 7. With the surface 3 hooked over the rim4 and the locking cam 9 in place against a rim, the leveling cam 10 isalso moved counterclockwise so that the surface 11 securely locks thecam 9 with the horizontal surface 13 of the rim. When a tire is beingplaced on a wheel, a very great force is exerted on the stop due to pullof stretching the tire bead in attempting to place it on the rim, andthe leveling device prevents the bead stop from tilting and being pulledoff the rim.

The bead-dropping assembly of the tire-mounting structure is illustratedin Fig. 5. The dropping structure includes an .arcuate body which isarranged to seat substantially horizontal on a horizontally-held wheel,and a rim-hooking portion or flange 21 extending laterally from the bodyand arcuately curved to correspond generally to the arc of the rim of awheel. The portion 21 ends in a pointed member 22 at one end, which isarranged to ride generally below the edge of the rim 4, and the upper,diagonal, connecting surface 23 between the point 22 and the surface 21extends upwardly into the body '20. The width of the surface 21 isreduced at the rear portion 24 thereof, and a shoulder 25 interconnectsthe two portions. An axially-extending portion 26 extends upwardly fromthe body 20 and it includes a front upright surface 27 and a diagonalbead-guiding surface 28 which extends from the upright surface 27 abovethe portion 24 rearwardly of the device. A radially-extending stop 29 ismounted above the upright surface 27 and is arranged to prevent axialmovement of the tire bead away from the wheel rim. A handle mount 30extending rearwardly of body 20 provides means for mounting a handle 31thereon.

In operation of the tire mounting assembly, illustrated in Fig. l, awheel, shown generally by numeral 33, is mounted in substantialhorizontal position over an upright center post 34, such as is commonlyused on many tire-changing machines. The head stop is locked on the rim4 of the wheel and a tire, shown in general by numeral 35, is placed onthe Wheel with the lower bead hooked over the upright section 2 of thestop. The bead drop device is then placed on the rim 4, with the portion21 hooked over the rim, at a point on the rim closely spaced to thestop. The lower bead of the tire is placed on the body 20 adjacent theupright surface 28, along the upright 27 and under the bead stop 29. Thehandle 31 is then moved in a clockwise rotation so that the surface 28moves along the lower tire bead forcing it across the upright 27, downacross the body 20 onto the lower surface 24 and subsequently into thedrop center of the wheel. The head drop mechanism is rotated around thewheel to progressively drop the head of the tire over the rim into thedrop center. As the head is prevented from moving by the stop, and sinceit is held by the upright 2, the bead at that point is adjacent but doesnot touch the rim. The head follows along surface 28, down over thesurface 24 into the drop center of the wheel and the head is thus placedover the rim Without touching the rim during the mounting operation. Themovement of the bead-drop is continued around the rim until it, isclosely adjacent the other side of-the stop at which point the bead ofthe tire will be completely in the drop center of the wheel. The headdrop is then removed, again placed on the other side of the stop and theupper bead of the tire is then placed in a similar position on the stop1 and on the body 20 against the-diagonal surface 28. The handle 31 isagain rotated in a clockwise direction, dropping the upper head ofthetire into the drop center of the wheel. When the bead drop mechanismis on the other side of the stop, the upper head of the tire will be inposition in the drop center of the wheel and the tire is mounted. Inboth cases of mounting the bead over the rim of the wheel, the bead ismoved across smooth surfaces of the tire mounting mechanism withouttouching the rim during the mounting operation, thereby reducingsubstantially the possibility of damage to the bead.

The bead stop may be utilized in holding a bead stationary on a rimwhile placing the head in the drop center of a wheel, utilizing mosttypes of tire-mounting equipment; however, the unique'ability to dropthe bead over the rim of the wheel without touching the rim during .theoperation is not achieved without the use of .the beaddrop tool of theinvention. Likenn'se, the bead-drop tool may be used without the stopduring the mounting op eration, but the benefit of passing the bead overthe rim without touching the same is not achieved without thecombination of the two devices which shield the rim as the bead isdropped thereover.

While the invention has been illustrated by reference to specificdevices, there is no intent to limit the scope or the spirit of theinvention to the precise details so set forth, especially as thepreferred form shown is a simplified form with the mounting tool made intwo separate pieces, since it is obvious that the two may be joined intothe single tool, and also, various means may be utilized to fasten thebead-stop mechanism to the rim of the wheel.

I claim:

1. A new article of manufacture for placing a tire head over a dropcenter wheel rim without contacting the same during mounting operation,comprising a substantially thin planar body arranged to slidably seat onand cover a minor portion of a wheel rim and having an integral curvedportion extending laterally from one side of said planar body inposition to hook over a rim, a portion projecting from said curvedportion beyond said body including a pointed portion arranged to ridebelow a rim, a lateral upstanding wall portion diagonally projectingfrom the other side of said planar body and extending to an edge of saidplanar body, said upstanding wall arranged to guide a tire bead ontosaid curved portion, the end of said curved portion opposite saidpointed portion terminating below and rearwardly of said upstanding wallso as to place a bead in the drop center of a held wheel, and means formounting a manipulating member on said body for rotating the same arounda rim.

2. Structure for placing the beads of pneumatic tires over the rim ofdrop center wheels without contacting such rims during mounting,comprising a substantially planar body for slidably engaging the side ofthe rim, an upstanding wall portion diagonally extending across one sideof said body, a gently curved portion depending from the opposite sideand extending along substantially one entire edge of the body inposition to hook over the edge of the rim and terminating in a pointedportion below said body, the end of said curved portion opposite saidpointed portion being terminated below and rearwardly of the point ofintersection of said upstanding wall with said curved portion, and meansfor mounting a manipulating member on said body for rotating the samearound a rim.

3. Structure for placing the beads of pneumatic tires over the rim ofdrop center wheels without contacting such rims during mounting,comprising a substantially planar body for slidably engaging the side ofthe rim, an upstanding wall portion diagonally extending across one sideof said body a gently curved portion depending from the opposite sideand extending along substantially one entire edge of the body inposition to hook over the edge of the rim and terminating in a pointedportion below said body, the end of said curved portion opposite saidpointed portion being terminated below and rearwardly of the point ofintersection of said upstanding wall with the curved portion, a radiallyextending stop portion mounted on a front upright surface connected tosaid wall portion, and means for mounting a manipulating member on saidbody for rotating the same around a rim.

4. The structure as defined in claim 3, in which the radially extendingportion is at a point spaced above and beyond a rim on which saidstructure is mounted.

References Cited in the file of this patent UNTTED STATES PATENTS

